Costa has actually been the standout player in Atletico's extraordinary season to this day, with his 26 objectives in 31 Primera Division matches offering his side an outstanding chance of winning their first league title considering that the 1995-96 campaigns.
It is for that reason unsurprising that the Brazil-born Spain international has actually drawn in the focus of numerous leading European clubs, and Jose Mourinho's Blues are apparently at the front of the queue.
It would take a significant offer for Atletico to consider selling their prize property, although Simeone believes Costa will ultimately decide his own future.
"It lies on him and exactly what he believes is best for him and his future. I will support any decision," the Argentine mentioned to AS.
"It is normal that Chelsea want him. They have good economic potential. Eto'o is getting older and Diego Costa can do his work, however today he's ours.".
Costa will be hoping to showcase his talents versus Chelsea in the Champions League semi-finals, a clash that has been made more fascinating by the prospect of the Blues' own goalkeeper ending up for Atletico.
Courtois is on loan at Atletico for a 3rd successive season and Chelsea insist he will be complimentary to bet them, in line with UEFA rules, as the clubs contend for a place in the May 24 last in Lisbon versus Real Madrid or defending champions Bayern Munich.
It was reported that Chelsea would permit the Spanish side to play the Belgian in both legs of the semi, provided they paid a fee of around 3million euros for each game.
However, UEFA transferred to clarify that it anticipates Courtois to be free to deal with cries in both legs and Simeone has no doubt that the 21-year-old will be readily available for choice.
"I have no doubt that he will bet Chelsea. He also has no doubts. Not a concern," Simeone stated.
There has been some idea Courtois might be made use of as a makeweight if Chelsea do pursue their interest in Costa, however Simeone does not know whether the Belgian's future lies at the Vicente Calderon.
"It is not yet known where he will play next year," he included.
